Jude:6-7

6 Angels who didn't keep their first domain, but deserted their own dwelling place, he has kept in everlasting bonds under darkness for the judgment of the great day.  7 Even as Sodom and Gomorrah, and the cities around them, having, in the same way as these, given themselves over to sexual immorality and gone after strange flesh, are set forth as an example, suffering the punishment of eternal fire.